PageControl&ScrollView Combination - ios

Question

I am a new coder in iOS. When I was trying to code ScrollView with paging, there is an issue to be fixed. I really don't know what is the problem in my code. I already set pageEnable, and set the page number with 4 current 0. In xib.file, I created 4 views, make scrollview connect "delegate" to "file's owner". My reference link http://www.iosdevnotes.com/2011/03/uiscrollview-paging/
When I run the app, the view cannot be paged.
Thank you for your help.
Here is my code:
////////// I think there is a problem in the for loop in viewDidLoad.
import
#interface ThirdViewController : UIViewController {
IBOutlet UIScrollView *scrollView;
IBOutlet UIPageControl *pageControl;
IBOutlet UIView *contentOne;
IBOutlet UIView *contentTwo;
IBOutlet UIView *contentThree;
IBOutlet UIView *contentFour;
}
- (IBAction)pageValueChange:(id)sender;
#property(nonatomic,strong) IBOutlet UIScrollView *scrollView;
#property(nonatomic,strong) IBOutlet UIView *contentOne;
#property(nonatomic,strong) IBOutlet UIView *contentTwo;
#property(nonatomic,strong) IBOutlet UIView *contentThree;
#property(nonatomic,strong) IBOutlet UIView *contentFour;
#property(nonatomic,strong) IBOutlet UIPageControl *pageControl;
#property(nonatomic,strong) NSArray *viewArray;
#end
#import "ThirdViewController.h"
#interface ThirdViewController ()<UIScrollViewDelegate>
#end
#implementation ThirdViewController
#synthesize scrollView,contentOne, contentTwo,contentThree,contentFour,pageControl,viewArray;
- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
if (self) {
self.title = NSLocalizedString(#"Profile", #"Third");// Custom initialization
}
return self;
}
- (void)viewDidLoad
{
[super viewDidLoad];
viewArray = [[NSArray alloc]initWithObjects:#"contentOne",#"contentTwo",#"contentThree", #"contentFour",nil];
for (int i =0; i < [viewArray count]; i++) {
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * i ;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
UIView *subview =[[UIView alloc]initWithFrame:frame];
[self.scrollView addSubview: subview]; //////how to pass the array object to subview
[subview removeFromSuperview];
}
// Do any additional setup after loading the view from its nib.
scrollView.contentSize = CGSizeMake(scrollView.frame.size.width *[viewArray count], scrollView.frame.size.height);
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (IBAction)dismissKeyboard :(id) sender{
[sender resignFirstResponder];
}
- (IBAction)pageValueChange:(id)sender{
CGRect frame;
frame.origin.x = self.scrollView.frame.size.width * self.pageControl.currentPage;
frame.origin.y = 0;
frame.size = self.scrollView.frame.size;
}
#pragma mark -UIScrollView Delegate
-(void)scrollViewDidScroll:(UIScrollView *)sender{
CGFloat pageWidth = self.scrollView.frame.size.width;
int page = floor((self.scrollView.contentOffset.x-pageWidth/2)/pageWidth)+1;
self.pageControl.currentPage = page;
}
#end

Answer 1

Did you put a breakpoint next to the line it crashed on?